The instant invention generally relates to mechanisms for filling and discharging fluid from a tank and more particularly to such discharge mechanisms that first add fluid to a tank and then discharge that fluid, leaving the tank discharged thereafter until the next fill and discharge cycle.
A number of devices, including toilets, incorporate a means for discharging a metered volume of fluid, and for also metering the amount of fluid that will be discharged. In many of these devices, metered volume of fluid is held by a holding tank until such time as discharge means is activated for discharging the tank. By use of the holding tank, different fluid flow rates may be used for the filling and discharge processes. For example, with a toilet tank, the toilet tank is typically filled at a relatively slow rate and then discharged at a relatively fast rate for purposes of flushing the toilet, wherein the relatively fast rate of discharge is needed for effectively flushing the toilet bowl. In systems for which the holding tank is normally filled with fluid, the tank is in a state that is ready for discharge, so that the discharge process is responsive to the activation thereof, without substantial delay.
A number of problems are associated with tank discharge mechanisms for which the tank is normally filled with the fluid to be discharged. For example, a holding tank filled with cold fluid is subject to condensation on the outside of the tank. Further, the holding tank filled with fluid is subject to leakage and wastage if the discharge valve does not seal properly, as is common with many toilets, for example as a result of a sticking discharge handle or a problem with the chain linkage between the float and the discharge valve. Yet further, if the temperature of the fluid is substantially different from the surroundings, there can be substantial heat transfer with the surroundings during the period from when the time the tank is filled until when the tank is flushed. The temperature of the fluid in a normally filled tank will tend towards that of the surroundings, which if different from the initial temperature of the fluid can be a problem in systems for which the temperature of the discharge fluid is preferably the same as that of the initial temperature of the fluid.
In accordance with a first aspect, a tank filling and discharge mechanism comprises:
(a) an inlet valve comprising a housing, a valve seat, and a first valve element moveable relative to the valve seat for opening and closing the inlet valve, wherein the inlet valve is operatively coupleable to a tank and to a source of fluid, whereby when the inlet valve is operatively coupled to the tank and to the source of fluid, the inlet valve admits the fluid to the tank when the inlet valve is open;
(b) a discharge valve comprising a second moveable valve element, wherein the discharge valve is operatively coupleable to the tank, whereby when the discharge valve is operatively coupled to the tank, when the discharge valve is opened, the fluid can discharge from the tank through the discharge valve;
(c) a coupling element operatively coupled to the first moveable valve element of the inlet valve and to the second moveable valve element of the discharge valve so that when the discharge valve is closed, the inlet valve is open; and when the inlet valve is closed, the discharge valve is open;
(d) an activation element operatively coupled to at least one of the coupling element, the inlet valve, and the discharge valve, whereby when activated, the activation element causes the inlet valve to open and the discharge valve to close;
(e) a first biasing element operatively coupled to at least one of the inlet valve, the coupling element and the discharge valve, whereby the first biasing element applies a biasing force to close the inlet valve;
(f) a retaining element operatively coupled to at least one of the inlet valve, the coupling element, and the discharge valve, wherein the retaining element comprises a clamp mechanism that releasably engages the at least one of the inlet valve, the coupling element, and the discharge valve; and
(g) a float, wherein the float is moveable relative to the coupling element; a position of the float is responsive to a fluid level in the tank; for the position below a first position, when the discharge valve is closed, the retaining element engages at least one of the inlet valve, the coupling element, and the discharge valve, so as to prevent the inlet valve from closing and the discharge valve from opening; for the position above the first position, the float engages the retaining element so as to cause the retaining element to release the at least one of the inlet valve, the coupling element, and the discharge valve, thereby enabling the first biasing element to close the inlet valve and open the discharge valve.
In accordance with a second aspect, a tank filling and discharge mechanism comprises:
(a) an inlet valve comprising a housing, a valve seat and a first valve element moveable relative to the valve seat for opening and closing the valve, wherein the inlet valve is operatively coupleable to a tank and to a source of fluid, whereby when the inlet valve is operatively coupled to the tank and to the source of fluid, the inlet valve admits the fluid to the tank when the inlet valve is open;
(b) a discharge valve comprising a second moveable valve element, wherein the discharge valve is operatively coupleable to the tank, whereby when the discharge valve is operatively coupled to the tank and the discharge valve is opened, the fluid can discharge from the tank through the discharge valve;
(c) a coupling element operatively coupled to the first moveable valve element of the inlet valve and to the second moveable valve element of the discharge valve so that when the discharge valve is closed, the inlet valve is open, and when the inlet valve is closed, the discharge valve is open, wherein the coupling element comprises a rod operatively coupled between the first valve element of the inlet valve the second valve element of the discharge valve, whereby the first and second moveable valve elements are moved by a translation of the rod;
(d) an activation element operatively coupled to at least one of the coupling element, the inlet valve, and the discharge valve, whereby when activated, the activation element causes the inlet valve to open and the discharge valve to close;
(e) a first biasing element operatively coupled to at least one of the inlet valve, the coupling element and the discharge valve, whereby the first biasing element applies a biasing force to close the inlet valve;
(f) a retaining element operatively coupled to the coupling element, wherein the retaining element comprises a latch mechanism operatively coupled between the rod and the housing of the inlet valve that releasably engages the coupling element;
(g) a float, wherein the float is moveable relative to the coupling element; a position of the float is responsive to a fluid level in the tank; for the position below a first position, when the discharge valve is closed, the retaining element engages the coupling element so as to prevent the inlet valve from closing and the discharge valve from opening; for the position above the first position, the float engages the retaining element so as to cause the retaining element to release the coupling element, thereby enabling the first biasing element to close the inlet valve and open the discharge valve.
In accordance with a third aspect, a method of filling a tank with fluid and then discharging the fluid from the tank comprises:
(a) controlling an inflow of a fluid from a source of fluid into a tank with an inlet valve;
(b) controlling a discharge of the fluid from the tank with a discharge valve;
(c) operatively coupling the inlet valve to the discharge valve so that when the discharge valve is closed, the inlet valve is open; and when the inlet valve is closed, the discharge valve is open;
(d) applying a biasing force so as to tend to close the inlet valve;
(e) closing the discharge valve, thereby causing the inlet valve to open by the coupling of the inlet valve to the discharge valve, thereby admitting the fluid to the tank;
(f) providing a clamping force so as to hold the discharge valve closed against the biasing force;
(g) modifying the clamping force responsive to a buoyancy force, whereby when a level of the fluid in the tank is above a threshold, the biasing force is sufficient to overcome the clamping force, thereby closing the inlet valve and opening the discharge valve; and
(h) discharging at least a portion of the fluid from the tank through the discharge valve.
In accordance with a fourth aspect, a method of filling a tank with fluid and then discharging the fluid from the tank comprises:
(a) controlling an inflow of a fluid from a source of fluid into a tank with an inlet valve;
(b) controlling a discharge of the fluid from the tank with a discharge valve;
(c) operatively coupling the inlet valve to the discharge valve so that when the discharge valve is closed, the inlet valve is open; and when the inlet valve is closed, the discharge valve is open; whereby the inlet valve is opened and the discharge valve is closed by a translation of a coupling element in a first direction; and the inlet valve is closed and the discharge valve is opened by a translation of the coupling element in a second direction opposite to the first direction.
(d) applying a biasing force so as to tend to close the inlet valve;
(e) closing the discharge valve, thereby causing the inlet valve to open by the coupling of the inlet valve to the discharge valve, thereby admitting the fluid to the tank;
(f) providing a latching force so as to hold the discharge valve closed against the biasing force;
(g) modifying the latching force responsive to a buoyancy force, whereby when a level of the fluid in the tank is above a threshold, the latching force is released, thereby enabling the biasing force to close the inlet valve and open the discharge valve; and
(h) discharging at least a portion of the fluid from the tank through the discharge valve.